Thursday, February 20, 2014

How do I interpret my ovarian reserve test results ?

Modern IVF technology is very effective, and we are every good at making embryos , no matter how poor the sperm quality . The biggest challenge we encounter today is treating patients with poor ovarian reserve, because poor quality eggs result in poor quality embryos.

However, there’s a lot of confusion about testing ovarian reserve and egg quality. Just because a woman has poor ovarian reserve does not mean she will necessarily be infertile. After all, all testing has its limitations and flaws. Just like men with low sperm counts can father a pregnancy if their spouse is super-fertile , similarly young women with poor ovarian reserve can conceive on their own, if their husbands have excellent sperm count. Fertility is a complex issue, which is impacted by many biological variables, and it’s hard for anyone to predict future fertility for an individual couple.

So what does poor ovarian reserve mean ? Does this mean there aren’t enough eggs ? Or that the egg quality is poor ? Or does it mean that both the quantity and quality of the eggs have taken a hit ?

In the past, the only way we had of assessing ovarian reserve was based on the patient’s history. We know that older woman have poorer ovarian reserve as compared to younger women; and that endometriosis and ovarian surgery damaged egg quality.

Today, we have better ways of testing ovarian reserve . These include : blood markers for egg quality; vaginal ultrasound ; and the clinical response to treatment. Let’s look at these one by one.

For many years infertility specialists used Day 3 FSH levels to test for ovarian reserve. The trouble with this test was that FSH levels depended on which day of the cycle they were drawn. They often varied from cycle to cycle, and were not reliable, as they were suppressed by the estradiol in the blood. The clomid challenge test was more reliable, but never became popular.

A recent advance has been the AMH test. This is a simple and inexpensive blood test , for checking AMH levels. The problem is that this is a relatively new test, and we still don’t have enough clinical experience with it. Also, while it’s great for assessing groups of women, like any other test, it has limited predictive ability for the individual patient. Also, many labs do not provide trustworthy results, because of poor quality control, and patients often get confused.

A better test is checking the antral follicle count , using vaginal ultrasound scanning. While this is a very useful when done in a good center, many doctors are still not expert at doing this scan and do not report it properly. The AFC does correlate fairly well with ovarian reserve. However, the problem with this test is that we are not interested in follicles – we are interested in the quality of the eggs , which are inside the follicles and which cannot be seen by ultrasound scanning , because they are microscopic. This means that all our tests provide indirect assessments of egg quality, which is why interpreting them can be so tricky.

While good doctors will combine these results to counsel the patient, please remember that we can only provide a rough probability as to how many eggs you will grow.. Test results don’t allow doctors to become fortune-tellers – and there will always be patients who surprise us !

In the final analysis, the proof of the pudding is in the eating , and the clinical response of the patient to superovulation is the best test for ovarian function. This is why an IVF cycle can provide such valuable diagnostic information about egg quality. It allows us to directly assess the eggs, because we can actually check these in the IVF lab after retrieval; and this is the only method which allows us to check the functional competence of the eggs, because we can see how many of eggs go on to form good-quality embryos . While this is very helpful in a good IVF lab, sometimes even the results of an IVF cycle are invalidated because of a poor quality IVF lab, where even good quality eggs may fail to form good quality embryos, because of poor lab conditions.